Williams Sound T4 User manual

Williams
Sound Corp.
Personal PA/FM
Broadcasting System
Installation
and User Manual
for Transmitter Models
T4 and T4P
and Receiver Models
. R7 , R7-4, and R7\00

Personal PA / FM
Broadcasting System
INSTALLATION AND USER MANUAL
lhmsm ltter Controls and Features ................. . .•...•..•.... 1
Tran smitter Set-up and Operation • ..........• . .... . ... . ..... .. .. 3
Antenna Connection
.. •• •• •. •• . , ...•..•...... . ............. .3
Power Connection ..... . .......... . ........... . ... . .......•. 3
Audio Connection ........•............................. • ... 3
Using Microphone Inputs with the Model
T4P Transmitter .. . .. • .. • 6
Audio Level Check .....•. . . . .. . ..... . .... . ..... . ..••..•.•.. 6
Setting the " lo Cut" Switch .•... . ....... • . . .. • .. • .•. .. •. _ •.. 7
System Check-out
... .. ... . ......... • •.•.•... . .•............ 7
Receiver Instructions
........ . .•..................•........ . .. 8
Receiver Management ... . .................••.. . . . ..•.. . .....•. 9
Battery Information ............... . ......... . .......••.. .. .... 9
Remote Coaxi al Antenna Installation .................. .. .•.•.... 11
Troubleshooting for the Model T4 Transmitter . ....••. . ........•... 13
Troubleshooting f or the Model T4P Tra nsmi tt er ..... .• .. • . . .. . .... . 15
R ad io Interference Problems ..... . ......... . ... .. ...... . .. . .... 15
System Specifications .. ............... . ..... .. . . .... . ........ 16

Personal PA System Installation
INTRODUCTION
The Personal PA/FM Broadcasting System has been designed for easy
installation by persons with minimal
electroniCi: experiehce. Some ex-
perience with sound systems will be helpful. Please read the manual com-
pletely and pay close attention to the antenna location guidelines if the
remote antenna is used. Taking a few minutes now to read the instruc-
tions
wi ll save time and ensure proper system operation.
TRANSMITTER CONTROLS AND FEATURES,
MODELS
T4 AND T4P
Tt)ere are two Personal PA/FM Transmitter models. Look at the drawings
below to identity your Transmitter.
ON AUlllD
Model T4
Front Panel Jacks
The T4 Transmitter does not have microphone jacks on the front panel.
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Model T4P
The T4P Transmitter has three jacks on the front panel. "Mic 1;· '' Mic 2,"
and "Tape Out." The "Mic 1" and
"Mic 2" jacks are low-impedance, un-
balanced microphone inputs tor dynamic
or electret microphones. Both
microphone inputs are mixed together
in the Transmitter. The "T ape Out"
jack is a
1K Ohm line level output for tape recording or feeding a sound
system.
Front Panel Indicators
The Transmitter front panel has two indicator lights, "POWER" and
' '.AUDIO." The "POWER" light shows that the unit is on, and the ' '.AUDIO "
light indicates sufficient audio input level. Because the Transmitter draws
very little power, it ,does not have a power switch and can be left plugged
in continuously.
-1-

Rear Panel Controls and Connections
Model T4 and T4P have identical rear panel controls and connections. Refer
to Figure 1.
PERSONAL P,4/FM Tran.mllte< t.'odel PPA n
~ 12DVAC.
----d,j 50 / 60 Hl., lW
l o Cu<
Mlonllor Q I I
0 l:=J
'Mada 1111 U.S.A.
Figure 1
The "Hi-Z Line Input" is an unbalanced, high impedance input for line
level signals
(0.04 to 4 Vrms).
The "Lo-Z Bridging Line Input" is a balanced bridging input for line
level signals from professional balanced line systems. Both line inputs are
mixed within the Transmitter.
The "Input Atten" Switch is used with the '1\udio" indicator light to set
the proper line input level. The "0" (left) position does not attenuate or
reduce the line input level. The
"-20" (center) position attenuates the line
input signal 20 dB. The ·•
-40" (right) position attenuates the llne input
signal 40 dB.
The " Lo Cut" Switch provides low frequency attenuation. The "O " (left)
position does not reduce the low frequencies. The
"1" (center) position
is the recommended position and provides a slight low frequency cut ( -10
dB at 80 Hz). The ''2" (right) position provides a steep low frequency cut
( -10 dB at 240 Hz). The "Lo Cut" switch is used to temporarily overcome
hum problems produced by the sound system or to tailor the Personal
PA System frequency response. It is sometimes desirable to cut low fre-
quencies to improve speech intelligibility for hearing impaired listeners.
The _,Rem ote Antenna" Connector is a 75 Ohm, F-type connector for
the optional Coaxial Antenna.
The "Monitor" Jack is used to monitor the input signal to the Transmit-
ter stage. An
8-16 Ohm earphone or headphone plugs into the 3.5mm jack.

TRANSMITTER SET-UP AND OPERATION
Step 1. Install the Whip Antenna
The whip antenna fits into the hole on top of the Transmitter cabinet. Push
the antenna straight through the hole. The antenna threads onto a bolt
mounted on the circuit board. Guide the antenna onto the bolt and turn
it clockwise to tighten.
It only needs to be finger-tight. Extend the antenna
to its full height when ready for use.
Alternately, the optional half-wave Coaxial Antenna may be used instead
of the Whip Antenna if the system will be rack mounted. The Coax An-
tenna attaches to the connector labeled "Remote Antenna" on the back
of the Transmitter.
..
See page 11 for further instructions on using the Coaxial Antenna..
Step 2. Connect the Transmitter to Power
AC Power
Plug the power cord into a 120 Volt, 60 Hz outlet. There is no power switch
on the Transmitter, so it will be on continuously when it is plugged
in. The
green "Power" indicator on the front panel of the Transmitter should glow
when the power is connected,
Step 3. Audio Connections
Connecting the Transmitter to a sound system amplifier:
"The Hi-Z Line Input" is the most commonly used input connection. The
"Lo•Z Bridging Line Input" is used with professional balanced line sound
systems.
To use the "Hj.Z Line Input":
Locate the audio cable included with the system. It has an RCA connec-
tor on both ends. Plug one end of the audio cable into the Transmitter
''Hi-Z Line Input" jack. The other end plugs into an audio output jack on
the sound system amplifier or mixer. Suitable connections are:
1st Choice: "TAPE OUT" or "LINE OUT'' jack
2nd Choice: "BOOSTER"
or "BRIDGING" jack
3rd Choice: Speaker Terminal, 8 Ohm tap

---------
"Tape Out" or "Line Out Connection ":
Refer to Figure 2.
Make sure the jack is an OUTPUT jack. An INPUT jack will not provi de
the proper signal level.
Amplifier
or T~PE OU T
Mixer @
Figure 2
If you have a tape recorder connected to the " TAPE OU T" j ack , you may
order a Y-connector (Part No.WCA 003) from Williams Sound,
or purchase
one at a local stereo
or radio parts store. The Y-connector allows both the
tape recorder and Transmitter to
be plugged into the TAPE OUT jack as
in Figure
3.
To Power Unit
'(-C ONNECTOR To Tape Re corder
Figure 3
BOOSTER OR BRIDGING JACK CONNECTION
See Instructions for TAPE OUT
or LINE OUT connection.
NOTE:
Some amplifiers use 1/4" phone jacks for audio connections. If
your amplifier or mixer has this type of jack, you will need to order a
1/4 "
phone plug to RCA jack adaptor (Part No. CNA 007) from Williams Sound,
or purchase one at a local radio parts store.

Speaker Terminal Connection:
If the amplifier does not have a suitable line level output jack, the Transmit-
ter may be connected to the 8 Ohm speaker terminals. This type of con-
nection may be noisy or susceptible to interference. Do not connect the
Transmitter to a remote speaker location or interference is likely.
CAUTION! Do not connect the Transmitter to a 70 volt speaker terminal
or the unit will be damaged.
To connect the audio cable to the speaker terminals, cut off one of the
RCA plugs and strip the wires. Refer to Figure 4 for connection detalls.
Amplifier
SPEAKERS
Audio Cable
~ c:=::::::,.._J
Figure 4
To use the "Lo·Z Bridging Line Input":
The Lo-Z Bridging Line Input is a 10K Ohm, balanced bridging input for
connection to professional balanced line systems. Use a shielded cable,
and appropriate XLR connectors to connect the Transmitter to a balanced ,
line- l evel mixer or amplifier output. Refer to Figure 5 for connection details.
Mixer
LINE OUT
@)
Wiring Diagram, Microphone Cable
XLR
XLR
@
Audlo Cable • =)
..___ .... , LI --- -
!.----
• ----...
Figure 5
-5-

USING DIRECT MICROPHONE INPUTS WITH
THE
T4P TRANSMITTER
The T4P Transmitter has been designed to accep~ two low-impedance
microphones with 1/4" plugs. It can accommodate either dynamic or elec-
tret microphones. The microphone(s) plugs into the ''Mic 1" or "Mic 2"
jack on the front panel of the Transmitter. Williams Sound offers several
microphones for use with the
T4P Transmitter. If you wish to use a dif-
ferent microphone, follow these wirlng guidelines.
Dynamic Mies:
Use a Mono 1/4" Phone Plug.
Connect the positive (in-phase) lead
to the tip of the plug. Connect the
negative (return and shield) leads
to the sleeve of the plug.
Electret Mies Which Include a Battery:
Follow directions for Dynamic Mies above.
Electret Mies Without a Battery:
Use a Stereo 1/4" Phone Plug. Connect the positive (in-phase) lead to
the ring of the plug. Connect the negative (return and shield) leads to the
sleeve.
Do not make any connection to the tip of the plug.
If the microphone is connected properly, speaking into it should cause
t
he "Audio'' indicator light to flash. The two mic(ophone inputs are mixed
in the
T4P preamplifier stage. The microphone inputs are also mixed with
the line level input for voice-over effects, etc.
If the T4P is to be connected to a sound system, follow the directions given
for the standard-Model
T4 on page 3.
Step 4: Check Audio Level.
If you are using the T4 or T4P Transmitter with line inputs, you will now
need a program source for the Personal
PA. Have someone speak into
a sound system microphone or connect a tape player or radio
to play music
through the sound system. Make sure the sound system is on.
To check
the audio level:
1. Start with the "Input Atten" switch set to the -40 dB (right) position.
2. Plug one of the Receiver earphones into the "Monitor" jack. Listening
with the earphone, you should be able to hear the program source
clearly.
3. Watch the '1'.udio" lndlcator light on the front panel.
4. If the Audio light is not flashing, move the "Input Atten" switch to the
-20 dB (middle) position.
5, If the Audio
light still does not flash, move t~e "Input Atten" switch to
the odB (left) position.
- 6-

With the proper input level, the Audio indicator light will flash regularly,
in time with the program source. Optimum input signal level is
0.04 Volt
rms to 4 Volt rms. If you cannot achieve this input level with the '' Input
Atten" switch, you will have to adjust the level at the program source.
If you are using the T4P Transmitter with direct microphone inputs, set the
Input Attenuator Switch on the back panel of the
T4P Transmitter to the
"-40 dB" (right) position to reduce residual noise. The input attenuator
switch affects only the line level inputs. The "AUDIO" light should flash
when someone speaks into the Personal
PA microphone.
Step 5. Set the "Lo Cut" Switch
Start by setting the "Lo Cut" switch on the "1" (center) positioh. The "Lo
Cut'' switch affects both the microphone and line inputs. It can be used
to reduce hum from line level inputs
or to improve speech intelligibility for
hearing impaired listeners. Most hearing impaired listeners lose sensitivi•
ty to high frequencies. Setting the Lo Cut switch in the "1" or "2" positioh
flattens the perceived system frequency response. The
"Lo Cut" switch
function is detailed on page 2.
Step 6. Test the System with a Receiver
Open a Receiver box and install the battery and earphone, folloWing the
receiver instructions. Stand near the antenna and turn the receiver on.
Listen for the broadcast, using the program source you connected earlier.
If you can't hear the broadcast, first try another Receiver
or another bat-
tery. If you have ordered rechargeable batteries, note that they are shipped
in a discharged state. They must be charged for
14-16 hours before their
initial
use. If these suggestions don't work, consult the troubleshooting
section. ·
Step 7. Check the System Range
Slowly walk away from the antenna while listening with the Receiver.
Walk throughout the seating area to check the range.
You may find cer-
tain areas where the signal suddenly disappears. This is called a
"drop--
out" and is a normal occurence within a building due to reflections and
cancellations
of the radio signal. Moving slightly to the right or left will
restore the signal.
IF THE SYSTEM IS WORKING CORRECTLY:
The orange "Audio" light on the front of the transmitter should flash regular-
ly with the input signal. The signal should
be clear and undistorted in the
receivers. A slight amount of background hiss is normal. A hum
or buzz-
ing sound indicates a problem. System range should be 300 to 500 feet
between the transmitting antenna and the receivers.
-7-

PERSONAL PA RECEIVER INSTRUCTIONS,
MODELS - R7, R7M, R7-4 AND R700
Instructions for Models R7, R7M, and R7-4:
1. Plug the earphone into the jack. The listener should use the earphone in
their best ear. If the listener wears a hearing aid, they should remove
It and use the earphone in its place. For more severe hearing losses,
the listener may use the optional Neckloop_(Part No. NKL
001) with their
hearing aid if the aid is equipped with. a
"T " (telecoil) switch.
A variety of earphone and headphone devices are available from
Williams Sound to suit individual preferences and degrees of hearing
loss. See publication SPC
011.
2. Battery Installation or Replacement-Open the battery compartment
by lifting the thumb tab at the bottom ofthe Receiver. Connect the bat•
tery to the snap. Wind excess wire around the battery posts. Slip the
battery into its compartment and snap the lid shut. Avoid excessive
twisting or pulling on the battery wires.
3. Turn the Receiver on by rotating the control knob in the direction of
the arrow on top of the case.
Turn ing the knob in the direction of the
arrow will increase the volume. Turning the knob against the arrow will
decrease the volume.
To avoid battery drain, make sure the Receiver
is turned off when not in use. If the Receiver is left on, the battery will
go dead overnight.
4. For Models R7M and R7-4 , refer to the instructions included with the
Receiver for additional user information.
Instructions for' Model R700 Monitor Receiver:
1. Plug the R700 power cord into a 120 VAC , 60 Hz electrical outlet.
2. Attach the wire antenna (included)
to the antenna connector on the rear
panel of the receiver.
3.
Turn the power switch on and turn the volume co nt rol up until you hear
the signal from the transmitter.
4. Optional antennas are available to extend the pick-up range of the R700 .
The ANT 003 Mic-Stand Antenna or the ANT 006 Coaxial Antenna,
may be used with R700.
5. An external loudspeaker may be used instead of the lnternal
loudspeaker in the R700. Connect the (+) terminal of the loudspeaker
to the tip connection of a
¼" mono phone plug. Connect the (- ) ter-
minal of the loudspeaker to the sleeve connection of the
Y4 '' phone
plug. The R700
Will deliver approximately 1W maximum Into an 8 Ohm
speaker.
- 8-

SUGGESTIONS FOR THE MANAGEMENT OF
WILLIAMS SOUND PERSONAL
PA RECEIVERS
Receiver Distribution
We suggest that the regular users of the receivers either be given or be
allowed to purchase their own receivers, rather than asking for one each
time. In that
way, they need not call undue attention to their hearing loss.
They can also assume the responsibllity for battery maintenance and
keep-
i ng the earphone sanita ry . A visitor or infrequent user can obtain one from
an usher, who wi
ll have extras.
Some customers have reported success with other arrangements. They
issue earphones to the regular users but keep all the receivers on the
premises. Some also assign receivers to individuals and designate their
name with marking tape on the receiver, keeping both the receiver and
earphone together for their regular users.
Earphone Sanitation
The earphone supplied with Williams Sound receivers have replaceable
earpads.
Foam and fabric earpads can be washed in a
mUd detergent, rinsed, and
air dried. Replacements are available if they become worn or lost.
BATTERY INFORMATION FOR RECEIVERS
In normal use, a transistor-type battery will last about 25 hours. When the
sound becomes weak ordistorted, replace the battery. Do not leave a dead
battery in the Receiver.
We recommend a "transistor-type" battery such
as the Eveready
216 for replacement. Heavy duty alkaline batteries will
work fine, but they are more expensive ahd will not offer greater economy
in th is application.
Rechargeable Batteries
The FM Receiver can also use a rechargeable nickel-cadmium battery
available from Williams Sound. Gtven proper care, the rechargeable bat-
teries will give hundreds of hours of service and eliminate the problems
of dead batteries.
In normal use, a rechargeable battery will last about four
hours per charge.
NOTE: Rechargeable batteries are sh ipped in a discharged state. They
must be charged
14-16 hours prior to initial use. DO NOT ATTEMPT 10
RECHARGE NON-RECHARGEAB LE BATTERIES!
-9-

To charge the rechargeable batteries
The battery may be charged without removing it from the FM Receiver
by using the charger and charger cord. If the charger and charger cord
are separate, attach the battery snap on the charger cord to the charger
snaps. Some chargers have the charger cord permanently attached. Plug
the end of the charger cord into the earphone jack. Make sure the Receiver
is turned off while recharging the battery. Plug the charger into an un-
switched wall outlet and charge
14-16 hours or overnight.
Using the
BAT 012 Multiple Charger Case
The
BAT 012 Charger is designed to charge 1g receivers simultaneously.
To use the charger, make sure all receivers are turned OFF. Plug the
charger cords into the earphone jack on each receiver. Plug the wall
transformer into a wall outlet and charge the units for
14 to 16 hours.Once
the receivers are charged1 unplug the charger. Leaving the receivers on
a constant charge can shorten battery life.
Rechargeable Battery Care
For maximum performance and long life, rechargeable batteries should
be charged at least once a month, even if they are not in
use. It is a good
practice to let the batteries discharge completely before recharging.
Char1;r
ing for 14 to 16 hours is sufficient to fully recharge the battery.
A fully charged battery will give about4 to 5 hours of continuous use. The
sound will become weak and "flutter" when the battery needs charging.
If properly cared for the battery can be recharged hundreds of times.
To conserve the battery, make sure the Receiver is OFFwhen not in use.
Avoid shorting the + and -terminals together with metal objects. Bat-
tery damage can result.
-10--

REMOTE COAXIAL ANTENNA INSTALLATION
The optional ANT 005 Coaxial Antenna is intended for use with rack-
mounted transmitters or in installation areas where a remote antenna is
needed for maximum coverage .
CAUTION! Do not cut or alter the Antenna Cable before reading the in-
struct i ons below.
The ANT 005 Antenna Cable is alength of coaxial cable with an "F" .co n-
nector on one end and an 80 inch antenna built onto the other end . The
last 80 inches of the antenna is covered with nylon braid. This is the ac-
tive antenna element. The active element should never be altered . The
remainder of the Antenna Cable is RG-59 coax feedline. The feedline can
be shortened if you have the tools to install a new F-connector .If you need
a longer feedline , extension cables are available from Williams Sound in
50 foot lengths (Part No. WCA 008 50). Do not splice the cable to lengthen
it. Use the proper connectors .
Remote Antenna Location Guidelines
You will want to select an antenna location that is i nconspicuous, but still
provides adequate range . For max i mum signal strength , it is best to select
an antenna location somewhere within the listening area . The preferred
antenna location is towards the front of the listening area and above the
seats, if possible. The active element (nylon braid covered port i on) of the
Antenna should be kept straight, not coiled. Try a vertical ori entation first.
You may have to experiment with antenna orientation and location to
achieve maximum range. Try temporarily taping the antenna in a corner,
behind a partition, along a piece of wooden moulding, or along a ceiling
beam . You can also allow the antenna to hang freely , with a small weight
attached to the end to make it hang straight .
Avoid placing the antenna on steel beams or near structural steel
elements. Metal plaster lath , ductwork. and foil-backed Insulations
will absorb radio frequency energy, greatly reducing the range of the
Transmitter. A little time spent experimenting with antenna location
will ensure maximum range .
Install the Transmitter near the other sound equipment. Keep audio cable
length to a minimum . Make sure the Transmitter is connected to a three-
wire , grounded outlet. For professional rack installations, the Rack Panel
Mounting Kit (Part No. RPK 003) should be used .
-1 1-

Mounting the Coaxial Antenna
The coaxial cable portion of the Antenna Cable rnay be mounted withthe
3/16" brown nylon clamps and brown No. 6 x 1/2
1
' screws provided in the
hardware kit. Drill 3/32" holes, 3/8" deep for the clamps and screws, ap-
proximately every 3 to 4 feet. It you need to pass the cable through a wall,
a 1/2
11
hole size is necessary to pass the cable connector through. When
mounting the Antenna Cable, observe the following instructions:
• Do not bend the cable sharply at the connector.
• Do not staple the cable
in place.
• Avoid tight turns with the cable: allow
at least a 3
11
radius for turns.
The coaxial cable•portion of the Antenna Cable may be run in a conduit
with other audio wiring. However, to avoid radio frequency feedback, do
not run the cable in a conduit with microphone cables. Do not run the
cable
in a conduit with AC powerwires. To do so is hazardous and in v1ola-
tion with the National Electrical Code.
:J/ 16 Clamp
3-5116 Clam .PS 2-
118 Clamps
0 0 0 0
f-- 3-4 ' --t- 20·+ 20·+ 20· + 20· ~
ANTENflA MOUNTING
Figure 6
Antenna Cable Connection
Run the Antenna Cable from the antenna location to the Transmitter. If
the Antenna Cable is not long enough to reach the Transmitter, use one
or more 50 foot Extension Cables (Part No. WCA 008-50). The Extension
Cables connect between the Antenna Cable and the Transrnitter.
Refer to Figure 7 for connection details.
Be careful that the small inner wire
on the Antenna Cable enters
the hole in the center
of
Figure 7
the receptable. The con-
nectors screw together
and only need to be
finger-tight.
ANTENNA CONNECTION
-12-

"Outdoor Antenna System -If this transmitter is intended for connection
to an outdoor antenna system or possibly a single outdoorantenna, then
they must be installed to provide some protection againstvoltage surges
and built static charges. Articles
810 and 820 of the National Electrical
Code, ANSI/NFPA
70 -1984, provides information with respect to wire to
an antenna discharge unit, and the coaxial cable system; and with respect
to the size of grounding conductors, location of antenna-discharge units,
connection to grounding electrodes, and the requirements for grounding
the electrode (all for a possible outside antennasystem). If
an outside anten-
na is connected to the antenna terminal of the transmitter, be sure the
antenna system
is grounded in a manner similar to the accompanying
Figure."
STANDOFF
INSULATOR Sb
TO EXTERNAL ANTENNA
TERMINALS OF PROOUCT
GROUND CLAMPS
BONDING JUMP£Rd
OPTIONAL ANT€NNA GROUNDING ELECTRQDE
\
DRIVEN 8 FEET (2.4'1m) INTO THE EARTH
IF" REQUIRED 8Y LOCAL COOES. SEE NEC
S2898
SECTION 810 - 2l(ft
•u .. No . 10 AWG (5 .l 'IW'l'I ._,, Ha. I AWG c, .• ....,z> •""'1 l ~Ul!I , No . '17 ... we (1 .0 ..,,..2, coppe,.., l act ,neel o, bron,e ""··· o,
larpr, • • 8'°""" Wlra.
bs.cur• antenna .._.In MCI g,ound .,.,._ lo hoUM olllll lllncl-oll lflou!liloni .,_d from 4-1 IHI (t , :12 - 1.13 m)-rl .
clolount 1111lenna ditcharte unit H clou u _.ibl• lo wllera INd-ln an1ara houa, .
du .. ium- wl,. not """'lier 11Yn Ho. • AWC. 113 ,3-mm2) copper, or rhe ~ulvaltnl, when• Nperal• 1n1anna11roundl1111 alotclrocle
I•., _ _ SN NEC SecUon ,10-z1U).

TROUBLESHOOTING GUIDE FOR THE T4 TRANSMITTER
Re-read the Installation procedure and check your wi ri ng for errors. Most
problems are caused by failure to read or follow the installation
procedure.
"CAUTION:
To avoid electric shock do not perform any servicing
other than that contained
in this Troubleshooting Guide unless you
are qualified to do
so. Refer all servicing to qualified service per-
sonnel."-
Symptom: Transmitter "Power" light not on.
1. Make sure the Transmitter is plugged in.
2. Make sure the electrical outlet is on.
Symptom: Hum or buzz in system
1. Make sure the Transmitter and sound system amplifier are plugged in-
to 3-wire, grounded outlets.
2. Check installation for ground
loops. Try using a two-prong isolation adap-
tor on the Transmitter plug. Do not connect the adaptor ground lead.
3. It ground loops have been eliminated and the hum persists, move the
Transmitter ''Lo Cut" Switch to the
"1" (middle) position. If there is still
a hum, move the
"Lo Cut" Switch to the "2" (right) position.
NOTE: Using the "
Lo Cut" Switch to reduce hum is a temporary remedy,
Excessive hum is an indication of problems ln the sound system which
should
be checked by a qualified service technician.
Symptom: Buzzing in system
1. Some types ofsound system amplifiers (Bogen in particular) are suscep-
tible to RF pick-up from the
PPA Transmitter. This causes a buzzing
sound rn the p.a. system. The problem can be corrected by solde ri ng
bypass capacitors directly across the power supply rectifiers in the
amplifier. This work should be performed by a qualified service technl-
cian.
To eliminate the buzz, solder one . 01 ufd, 200 Volt ceramic disk
capacitor directly across each rectifier.
Symptom: Weak, noisy sound.
1
.. Try moving the •: tnput Atten" Switch to the "0'' or "- 20'' position.
2. Check for adequate audio signal level as described on page 6.
3. Measure the input signal level. Proper level should be .04 to 4 Volt rms.
3a. 11 the signal level is not correct
1. If your sound system amplifier has separate microphone controls
and a master gain control, turn the microphone controls up and
the master gain control down.
If the audio level is excessive, reduce
the microphone controls and increase fhe master audio gain to
restore the loudspeaker volume.
2. Try an alternate audio connection as shown on page 4.
-14-

Symptom: No sound in Receiver or very limited range.
1. Make sure Receiver is work1ng properly. See page 7.
2. Make sure antenna is connected to transmitter.
3. Review section on antenna installation and especially antenna loca-
tion if coaxial antenna is used.
4. Check for adequate signal level as described on page 6.
Symptom: "Scratchy" noise when Receiver volume control is adjusted.
1. Open back of Recelver ca_se by opening the battery compartment and
lifting ,the battery compartment flap up and to the left.
2. Remove screw from top of volume control knob and remove knob.
3. Lift clear plastic cover on top of exposed volume control.
4. Spray GC SPRA-KLEEN (Catalog No. 10-8666), LPS Contact Cleaner,
or equivalent into the volume control.
5. Replace volume control plastic cover, control knob, and screw.
6. Rotate the knob several times. If the noise persists, repeat the above
steps.
TROUBLESHOOTING GUIDE FOR THE T4P TRANSMITTER
Symptom: System does not operate. Green "Power" light not on.
L Make sure the Tran sm itter is plugged in . Make sure the outlet is
good by plugging in a lamp.
Symptom: Amber "Audio" light does not flash with input signal.
1. Make sure the microphone is plugged in . Make sure the microphone
is wired properly and works. Substitute a known good microphone.
2. Plug an earphone into the ' :A.udio Test" jack on the back oftheTransmit-
ter. When someone speaks into the microphone, you should be able
to hear them through the earphone.
Symptom: Signal "drops out'' in certain areas.
1. Transmitter location can affect drop-outs. Try rnoving the Transmitter to
another location.
2. It may be necessary to use the coaxial antenna when maximum range
is needed.
See also the Model
T4 Transmitter Troubleshooting Section.
If
you cannot determine the cause of a failure, .contact your dealer for
assistance.
RADIO INTERFERENCE
Since no broadcast stations operate on the frequency of the Personal PA
Broadcast System, it is normally immune to radio station interference.
However, certain local conditions can combine to create an interference
problem from other sources. Please contact your dealer or Williams Sound
for help, because further corrective action is dependent upon a technical
understanding of local conditions. Usually, changing the system frequen-
cy will clear up the problem.
-1 5-

PRODUCT SPECIFICATIONS
SYSTEM OPERATING FREQUENCIES
Channel
Frequency ("1 Hz)
A
72.1
B 72.3
C
72.5
D 72.7
TRANSMITTER MODEL T4, T4P
ltansmltter, Physical:
Dimensions: 6-1/2" W4 2-1/2 " H x
6" D
Weight 1.6 lbs .
Audio Specifications:
Balanced Bridg i ng , 10K Impedance
filma le XLR
Unbalanced, 100+< Impedan ce ,
RCA Jac k
Input Level : 0. 04 to 4 Vrms , nom i nal
Automatic Gain ConrrQI : 40 dB ran _ ge ,
30 rrN ltlreshold
Input Atte~uator : 3 .position s,
"0' ' = -3 dB at 10 1-fz ,
'' 1" = -10 tlB al 80 Hz,
"2" = -10 dB at 240 Hz
Monitor Jack : 3.5 mm Jack , 8- 32 Ohm s
Microphone - two 1/4" p~one jacks ,
{T4P only) !ow impe dance
lape Output - 1/4 " phone jack {T4P only)
1K impedance, line level
RF Specifications :
Max . DC Power Supplied to Fi nal
RF S~ge : 250 mW
Max . Transmitted Reid Strength :
8000 uV/m at 30 m
Operating Frequency ; 72 .1 to 75 .9 Mhz
Ftequency Stability : ±. 005%
Maximum Deviation ; + 75 k Hz
Pre-Emphasis : 75 us -
S/N Ra~o : 60 dB
Antenna
42" Telescoping , Whip
Optional 80 " Half - Wave Coaxial Antenna
Feedline: RG 59 Coax , 75 O~ rn
Channel
Frequency (MHz)
E 72.9 (Standard)
F 75.5
G 75.7
H 75.9
Transmitter Power:
AC Powe r: 100 to 130 VAC 50-60 H z,
2.5 W, AC Connect i on : 3-wire
grounded plug , 6' cord
RECEIVER MODELS R7, R7-4
Physical:
Dimen si ons : 3-5/8 " L x 2-318 " W ;,(
7/8 " H
Weight: 4 oz . wlltl · battery
Color : Burgundy
Elecll'ical:
Operating Frequency : R7 - Fixed ,
72 .1 to 75. 9 MHz
R7 - 4A - Preset to Channel s A, C, E, G
R7 - 4B · Preset to Channels B, D. F, H
De -E mphasis : 75 us
Sensilivity ; 2uV al 12 dB sr nad ,
squelch dereated
Frequency Response : 40 to 15 kHz+3 dB
Total Harm onic Distortion : 1.5% @
ra\!!d output
Power Output ; 250 mW max ,, @ 16 Ohms
Acoustic Outpu t: 130 db SPL max .
with EAR 013 @ 250 mW
Battery Type : One 9 Vo lt, Eveready 216 ,
Eveready 522 , or Varta TR 7/8
Battery Ute : Eveready 216
- 10 hours continuous
Eveready 522 - 17 hours continuous
Varta TR 7/8 - 5 hours/charge continuous
-16-

RECEIVER MODEL R7M
Physical:
Dimens i ons : 3-5/8" Lx2-3/8 " Wx718 " H
Weight: 4 oz. wi th battery
Color : Burgu ndy
Electrical:
Opera tin g F requency : Fix ed , 72 .1 to 75 .9
MHz
De - Emphas is: 75 us
Sensitiv i ty : 2uV at 12 dB Si nad ,
squelch defeated
Frequency Response : 80 to 15 kHz+3 dB
Total Harmon ic Di stortlon : 1.5% @
rated output
Power Ou tp ut: 200 mW max . @ 16 O hms
Acoustic Outpu t: 125 db SPL m ax .
wi th EAR 013 @ 2 00 mW
Max . Gain : Mi crophone • 60 dB , adjustable
FM- 40 dB ad j ustable
Battery T ype : 9 Vo lt, Eveready 216 ,
Eveready 522 , or Varta TR 7/8
Battery Life : Eveready 216
- 10 hours continous
Eveready 522 - 17 hours continuous
Varta TR 718 • 5 h ours/charge cont i nuous
RECEIVER MODEL R700
Pllyslcal:
Dimens i ons : 6-12 " Wx2-1/2 "Hx6"D
We i gh t: 2.1 l bs .
Co lor: Blac k
Electrical:
Ope rati ng Fr equency : Fi xed , 72 .1 to 75 .9
MHz
De - Empha si s: 75 us
Sensistivity : 2uV at 12 db Sinad , squelch
defeated
Frequency Response : 40 to 15 kHz+3 dB
Total Harmonic Distortlon : 1.5% @8 Ohm s
Powe r Ou tpu t: 120 VAC , 50-60 H z, :Ni
RACK PANEL MOUNTING
Rack Pane l Mounting Kit,
Model RPK 003
Dimensions : 19" W• 3 -112 " H• 8" D
Color : Bl ack
Specifica ti ons subjec t to cha n ge wi thout notice Copyrigh t 1989 , Will i ams Sou nd Corp .
-17-

.
Three Vear Warranty
Williams Sound products are engtneered and manuractured lo
give rnany yaars of trroub1A free service. Occasionally, latent
defects occur. If thfs happens, return the product to us with ship-
ping costs prepatd and advise us by letter of the observed dif-
· ~culty. During The tirst three years kJIIOl.!lling the date or pur-
chase, we will promptlyrepatr or rep la ce the product and return
it al our ~pense. After thrBe years from the dais of purchase,
wa will sewjce our products for a modest serllioo charge. Ftease
return the enclosed warranty card to register your date of pur-
chase. This warranty does not extend to physical damage. o,r
damage c.aiused by teakrng batteries. Microphones, earphones,
rechargeable batteries and chargers. headphonesand cables
are warranted for • go days . Unauthorized modifationsor reparrs
of the product will void the warranty.
Made in U.S . A.
,.~, ... .· Williams Sound Corp .
Mi nneasx,l"s., MmnesolB USA
1-8oo-J21M190
MAN 010E
Plln ed 111 U.S.A.